Most apartment buildings as well as many office buildings have reserved parking areas specifically for tenants of the building. In many cases, these reserved parking areas are left unattended and accessible to unauthorized use. In many instances, visitors to the building, who are unable to find any visitor parking will use the reserved parking spaces if they are not properly guarded.
There are presently available some different types of parking space guards in the form of blocking members movable between up and down positions. However, most of these guards are quite complicated in terms of their construction and the manner in which they are locked. Furthermore, even when in a down or access gaining position the blocking members are still subject to catching on the undercarriage of a car passing over them.
A further problem with presently available parking space guards is that the blocking members do not necessarily have a specific direction in which they are laid down to gain access to the parking space. This can present problems when the guard is located next to a sidewalk or close to the road where, if the blocking member is improperly placed, it can well block traffic.